Europeans couldn't travel into the interior of Africa in order to take it over because of the African-ruled trade, couldn't navigate violent rivers, or overpower their strong armies. Disease also held them back.
Albert Einstein is commonly associated with <span>physics. </span>
This is referred to as Nationalism. It is the notion or belief that one's country possesses qualities or traits not found in that of other nations. It often promotes a sense of exceptionalism and superiority; therefore, it has often led to <em>Chauvinism </em>which is a rather hostile form of Nationalism and is often utilised as a political tool to achieve an ends.
The answer is the first one.
Germany became two separate countries.
What I can infer from what Lewis and Clark saw when moving west from the Mississippi river is that the landscape along the river changed drasticallly. The forest receded, replaced first by the high prairie and then the shorter grass of the high plains. The temperatures became colder and as they continued their expedition by the river they realized that there was no water route to the pacific ocean, just more mountains.
